Fake food labels planted by Russian activists are warning shoppers against buying "hostile" Polish products.
A journalist for the Ekho Moskvy radio station, Svetlana Rostovtseva, found packets of herbs with the unofficial warning on the shelves of her local supermarket.
“Attention,” the label reads, “This product is produced in a country hostile to Russia.”
The herbs were originally grown in Poland before being sold by Russian supermarket chain Pyatorochka.
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Relations between Warsaw and Moscow have soured in recent years, with Poland pushing for an increased NATO presence along the country's eastern border.
The government recently exhumed the body of late President Lech Kaczynski as part of an ongoing investigation into the Smolensk air crash: a disaster which took place on Russian soil and saw the deaths of 96 people, including Kaczynski, his wife, and many senior Polish officials.
"It was just two packets," Rostovtseva wrote on Facebook, "and they weren't in their correct places. But yes, they were there."